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The present studies report erythropoietin (Ep) production in primary cultures of a human renal carcinoma from a patient with erythrocytosis that has been serially transplanted to BALB/c nude mice. The levels of erythropoietin in the culture media were estimated using the exhypoxic polycythemic mouse assay (EHPCMA), fetal mouse liver erythroid colony- forming technique (FMLC), and a radioimmunoassay (RIA). The spent culture media of the exponentially growing cells contained less than 10 mU/ml of Ep measured by RIA. However, after the cells became confluent, Ep levels (RIA) in the spent media showed a marked increase to approximately 300 mU/ml. Ep levels estimated using the FMLC and EHPCMA were approximately 2/3 and 1/10, respectively, of those measured by RIA. Rabbit antiserum to highly purified human urinary Ep (70,400 U/mg protein) was utilized for immunocytochemical (peroxidase-antiperoxidase method) localization of Ep in the cultured cells. Very few of the cells in exponential growth exhibited Ep-like immunoreactivity, whereas intense Ep-like immunoreactivity was observed in the cytoplasm of the cells maintained in culture for a prolonged period after reaching confluency. The most intense staining was observed in some of the cells forming domes. The domes developed after the cells reached confluency, and their numbers increased with increasing time in confluent culture, in parallel with the increase in Ep levels in the spent media. This primary cell culture system of a renal cell carcinoma maintained in nude mice, which produces immunologically and biologically active Ep, may provide a useful model for studies of the mechanism of Ep production.  相似文献   
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Bone and soft tissue sarcomas are a group of histologically heterogeneous and relatively uncommon tumors. To explore their genetic origins, we sequenced the exomes of 13 osteosarcomas, eight myxoid liposarcomas (MLPS), and seven synovial sarcomas (SYN). These tumors had few genetic alterations (median of 10.8). Nevertheless, clear examples of driver gene mutations were observed, including canonical mutations in TP53, PIK3CA, SETD2, AKT1, and subclonal mutation in FBXW7. Of particular interest were mutations in H3F3A, encoding the variant histone H3.3. Mutations in this gene have only been previously observed in gliomas. Loss of heterozygosity of exomic regions was extensive in osteosarcomas but rare in SYN and MLPS. These results provide intriguing nucleotide‐level information on these relatively uncommon neoplasms and highlight pathways that help explain their pathogenesis. © 2013 Wiley Periodicals, Inc.  相似文献   
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Fibromuscular dysplasia is a multifactorial arteriopathy most commonly affecting the renal and carotid arteries. In this report we present a case of visceral artery involvement, causing occlusion of the superior mesenteric artery and celiac trunk and resulting in visceral ischemia. Treatment consisted of superior mesenteric artery reimplantation. Visceral artery FMD can present as occlusive or aneurysmal disease and treatment depends on patient characteristics and symptoms.  相似文献   
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Background

High trait anxiety (HTA) causes an impaired quality of life (QOL) and fatigue in women with breast cancer (BC) and benign breast disease (BBD). We examined whether the lowered QOL was determined solely by the personality characteristic HTA or by the combination of personality and diagnosis.

Methods

In a prospective longitudinal study, women with BC (n = 152), BBD (n = 205), or gallstone disease (GD) before laparoscopic cholecystectomy (n = 128) were included. Questionnaires concerning trait anxiety (baseline), fatigue, and QOL were completed at baseline and at 6 months. Multivariate linear regression analysis was performed to analyze the predictors for QOL at 6 months.

Results

At 6 months QOL scores were increased in the GD group, especially in women without HTA. For women without HTA, in the BBD group the scores for fatigue and physical QOL had improved at 6 months, whereas in the BC group physical QOL and fatigue was impaired. Women with HTA scored unfavorably on fatigue and QOL. HTA was the most important factor influencing QOL.

Conclusions

The course of QOL and fatigue during follow-up were significantly different for each diagnosis. Particularly HTA had a negative impact on QOL and fatigue. Especially the combination HTA and BC caused impaired QOL and fatigue. We recommend identifying women with BC and HTA and offer them a tailor-made follow-up protocol.  相似文献   
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